Antibiotic use enhances the growth of healthy domesticated poultry and livestock. Although extensive bans and restrictions have not been implemented in the United States as they have in the E.U. and other countries, pressure for antibiotic alternatives has increased due to concerns of increasing antibiotic resistance among foodborne bacteria. Banning or markedly reducing the agricultural and farm-veterinary use of antibiotics may have a profoundly negative impact on the safety of foods and on the treatment of sick flocks or herds of domesticated livestock, however. Thus, effective, safe, and environmentally friendly alternative(s) to antibiotics are needed to address these concerns and needs.
Viruses that kill bacteria were first identified in the early part of the 20th century by Frederick Twort and Felix d'Herelle who called them bacteriophages or bacteria-eaters (from the Greek phago meaning to eat or to devour). Because of their remarkable antibacterial activity, phages were used to treat diseases of economically important animals/domesticated livestock almost immediately after their discovery, and therapeutic applications for humans closely followed. However, with the advent of antibiotics, phage therapy gradually fell out-of-favor in the United States and Western Europe, and virtually no subsequent research was done on the potential therapeutic applications of phages for bacterial diseases of humans or animals. The emergence of antibiotic-resistance in bacteria, however, has rekindled interest in therapeutic bacteriophages. Phage therapy may have a positive impact on human health by improving the safety of foods in the U.S.A. and elsewhere, and by helping to reduce safely the use of antibiotics in agribusiness.
Among the bacteria that cause significant morbidity and mortality in chickens, C. perfringens is one of the most notorious pathogens. In chickens, C. perfringens infections are often manifested as necrotic enteritis that occur later in the production cycle, often following a coccidial infection or other insult to the gastrointestinal tract. It is thus desirable to develop bacteriophage preparations suitable to reduce morbidity and mortality in chickens.